In many medical and cosmetic procedures there is a need to transfer fluids to areas below the surface of the skin, for example injecting insulin to diabetics and filling the dermal layer of the skin with collagens or other materials to preserve a youthful look. The most common method for introducing the fluids is by using a needle to inject the fluid to the desired position. The use of needles to administer the fluids requires that the administrator be trained to perform the procedure correctly so as not to cause damage. In many cases the exact position of injection is important to achieve the correct results. Generally, the use of needles causes damage to the skin and a significant amount of time is required for the damage to heal.
In recent years the injection of fluids using needle-less injectors has advanced. When using needle-less injectors, less training is required for a person to administer the injection, thus for example mass vaccination campaigns can be performed using untrained staff. Additionally, when using needle-less injections the penetration hole is generally smaller thus enabling the administration of more injections while minimizing damage to the surface of the skin. Additionally, newer skin augmentation methods rely on the self healing process of the skin, wherein the skin rejuvenates itself. In rejuvenation layers are thickened, and more collagen fibers are introduced. When using a needle damage is incurred to the skin surface but little trauma is caused to the cells of the internal layers of the skin, thus little rejuvenation is achieved.
A device that injects fluid subcutaneously or intradermally needs to be able to create a high pressurized jet of fluid with a small diameter so that it will be able to penetrate the epidermis layer of the skin. Generally, the device is more complicated than the common syringe for injecting fluids with a needle. Thus the needle-less injector tends to be heavier, more expensive and harder to control than the common needle injector.
Additionally, due to its simplicity and low cost the common needle injector is generally intended for a single use, thus preventing contamination and the spread of disease. In contrast the more complex needle-less device is mostly non-disposable and needs requires sterilization or additional precautions to prevent the transfer of contamination from one patient to another.